Heparan Sulfate-Collagen Surface Multilayers Support Serum-Free Microcarrier Culture of Mesenchymal Stem Cells.

The increasing cost of high-volume cultures and dependence on serum and growth factor supplementation limit the affordability of mesenchymal stromal cell (MSC) therapies. This has spurred interest in developing strategies that support adherent cell expansion while reducing raw material costs. Culture surfaces coated with sulfated glycosaminoglycans (GAGs), specifically heparan sulfate (HS), are an alternative to prolong growth factor retention in cell cultures. Unlike heparin, recombinant HS (rHS) offers strong binding affinity for multiple growth factors and extracellular matrix components, such as collagen I, without undesirable anticoagulant effects or xenobiotic health risks. The potential of rHS as a factor reservoir in MSC cultures remains underexplored. This study investigated the impact of rHS on the growth and anti-inflammatory properties of undifferentiated bone marrow MSCs in both planar and microcarrier-based cultures. It was hypothesized that rHS would enable MSC growth with minimal growth factor supplementation in a sulfation level-dependent manner. Cell culture surfaces were assembled via the layer-by-layer (LbL) method, combining alternating collagen I (COL) and rHS. These bilayers support cell adhesion and enable the incorporation of distinct sulfation levels on the culture surface. Examination of pro-mitogenic FGF and immunostimulatory IFN-γ release dynamics confirmed prolonged availability and sulfate level dependencies. Sulfated surfaces supported cell growth in low serum (2% FBS) and serum-free (SF) media at levels equivalent to standard culture conditions. Cell growth on rHS-coated surfaces in SF was comparable to that on heparin-coated surfaces and commercial surface-coated microcarriers in low serum. These growth benefits were observed in both planar and microcarrier (µCs) cultures. Additionally, rHS surfaces reduced ß-galactosidase expression relative to uncoated surfaces, delaying cell senescence. Multivariate analysis of cytokines in conditioned media indicated that rHS-containing surfaces enhanced cytokine levels relative to uncoated surfaces during IFN-γ stimulation and correlated with decreased pro-inflammatory macrophage activity. Overall, utilizing highly sulfated rHS with COL reduces the need for exogenous growth factors and effectively supports MSC growth and anti-inflammatory potency on planar and microcarrier surfaces under minimal factor supplementation.

Economic outcomes among microfinance group members receiving community-based chronic disease care: Cluster randomized trial evidence from Kenya.

BACKGROUND: Poverty can be a robust barrier to HIV care engagement. We assessed the extent to which delivering care for HIV, diabetes and hypertension within community-based microfinance groups increased savings and reduced loan defaults among microfinance members living with HIV. METHODS: We analyzed cluster randomized trial data ascertained during November 2020-May 2023 from 57 self-formed microfinance groups in western Kenya. Groups were randomized 1:1 to receive care for HIV and non-communicable diseases in the community during regular microfinance meetings (intervention) or at a health facility during routine appointments (standard care). Community and facility care provided clinical evaluations, medications, and point-of-care testing. The trial enrolled 900 microfinance members, with data collected quarterly for 18-months. We used a two-part model to estimate intervention effects on microfinance shares purchased, and a negative binomial regression model to estimate differences in loan default rates between trial arms. We estimated effects overall and by participant characteristics. RESULTS: Participants' median age and distance from a health facility was 52 years and 5.6 km, respectively, and 50% reported earning less than $50 per month. The probability of saving any amount (>$0) through purchasing microfinance shares was 2.7 percentage points higher among microfinance group members receiving community vs. facility care. Community care recipients and facility care patients saved $44.90 and $25.24 over 18-months, respectively, and the additional amount saved by community care recipients was statistically significant (p = 0.036). Overall and in stratified analyses, loan defaults rates were not statistically significantly different between community and facility care patients. CONCLUSIONS: Receiving integrated care in the community was significantly associated with modest increases in savings. We did not find any significant association between community-delivered care and reductions in loan defaults among HIV-positive microfinance group members. Longer follow up examination and formal mediation analyses are warranted.

Pregnant biglycan knockout mice have altered cardiorenal adaptations and a shorter gestational length, but do not develop a pre-eclamptic phenotype.

INTRODUCTION: Pre-eclampsia complicates 4.6% of pregnancies and is linked to impaired placentation; likely due to dysregulated vasculogenesis/angiogenesis. Proteoglycans, such as biglycan, are located on the endothelial surface of fetal capillaries. Biglycan is reduced in the placenta of pregnancies complicated by fetal growth restriction and pre-eclampsia. Importantly, biglycan stimulates angiogenesis in numerous tissues. Therefore, this study investigated whether biglycan knockdown in mice results in a pre-eclamptic phenotype. METHODS: Wild-type (WT) and Bgn-/- mice underwent cardiorenal measurements prior to and during pregnancy. One cohort of mice underwent post-mortem on gestational day 18 (E18) and another cohort underwent post-mortem on postnatal day 1 (PN1), with maternal and offspring tissues of relevance collected. RESULTS: Bgn-/- dams had increased heart rate (+9%, p < 0.037) and reduced systolic (-11%, p < 0.001), diastolic (-15%, p < 0.001), and mean arterial (-12%, p < 0.001) pressures at all ages investigated compared to WT. Additionally, Bgn-/- dams had reduced urine flow rate (-64%, p < 0.001) as well as reduced urinary excretions (-49%, p < 0.004) during late gestation compared to WT. Bgn-/- pups had higher body weight (+8%, p = 0.004; E18 only) and a higher liver-to-brain weight ratio (+43%, p < 0.001). Placental weight was unaltered with only minor changes in vasculogenic and angiogenic gene abundances detected, which did not correlate to changes in protein expression. DISCUSSION: This study demonstrated that total knockdown of biglycan is not associated with features of pre-eclampsia.

My Baby's Movements: a stepped-wedge cluster-randomised controlled trial of a fetal movement awareness intervention to reduce stillbirths.

OBJECTIVE: The My Baby's Movements (MBM) trial aimed to evaluate the impact on stillbirth rates of a multifaceted awareness package (the MBM intervention). DESIGN: Stepped-wedge cluster-randomised controlled trial. SETTING: Twenty-seven maternity hospitals in Australia and New Zealand. POPULATION: Women with a singleton pregnancy without major fetal anomaly at ≥28 weeks of gestation from August 2016 to May 2019. METHODS: The MBM intervention was implemented at randomly assigned time points, with the sequential introduction of eight groups of between three and five hospitals at 4-monthly intervals. Using generalised linear mixed models, the stillbirth rate was compared in the control and the intervention periods, adjusting for calendar time, study population characteristics and hospital effects. MAIN OUTCOME MEASURES: Stillbirth at ≥28 weeks of gestation. RESULTS: There were 304 850 births with 290 105 births meeting the inclusion criteria: 150 053 in the control and 140 052 in the intervention periods. The stillbirth rate was lower (although not statistically significantly so) during the intervention compared with the control period (2.2/1000 versus 2.4/1000 births; aOR 1.18, 95% CI 0.93-1.50; P = 0.18). The decrease in stillbirth rate was greater across calendar time: 2.7/1000 in the first versus 2.0/1000 in the last 18 months. No increase in secondary outcomes, including obstetric intervention or adverse neonatal outcome, was evident. CONCLUSIONS: The MBM intervention did not reduce stillbirths beyond the downward trend over time. As a result of low uptake, the role of the intervention remains unclear, although the downward trend across time suggests some benefit in lowering the stillbirth rate. In this study setting, an awareness of the importance of fetal movements may have reached pregnant women and clinicians prior to the implementation of the intervention. TWEETABLE ABSTRACT: The My Baby's Movements intervention to raise awareness of decreased fetal movement did not significantly reduce stillbirth rates.

Effect of dermatological consultation on survival in patients with checkpoint inhibitor-associated cutaneous toxicity.

BACKGROUND: Cutaneous immune-related adverse events (cirAEs) are a common side-effect of immune checkpoint inhibitors (ICIs). However, prior work examining these toxicities in detail has considered only the fraction of events evaluated by dermatologists. Associations between dermatology referral, cirAE treatment and survival outcomes remain underexplored across care settings. OBJECTIVES: To comprehensively categorize cirAE patterns among all patients treated with immunotherapy at our institution, and to evaluate: (i) the effect of dermatology referral on cirAE treatment and (ii) the impact of cirAE treatment on survival. METHODS: This was a retrospective cohort analysis of patients with cancer who initiated ICI therapy between 1 January 2016 and 8 March 2019 and developed one or more cirAEs, as screened for using International Classification of Diseases 10th revision codes and confirmed via manual chart review (n = 358). All relevant information documented prior to 31 March 2020 was included. RESULTS: CirAEs evaluated by dermatologists were significantly more likely to be treated than cirAEs that were not referred (odds ratio 6·08, P < 0·001). Patients who received any cirAE treatment had improved progression-free survival [hazard ratio (HR) 0·59, P = 0·001] and overall survival (HR 0·58, P = 0·007) compared with those who did not. CONCLUSIONS: CirAEs evaluated by dermatologists were significantly more likely to be treated than cirAEs that were not referred, and patients who received any treatment for a cirAE had improved survival outcomes.

Management of plantar heel pain: a best practice guide informed by a systematic review, expert clinical reasoning and patient values.

OBJECTIVE: To develop a best practice guide for managing people with plantar heel pain (PHP). METHODS: Mixed-methods design including systematic review, expert interviews and patient survey. DATA SOURCES: Medline, Embase, CINAHL, SPORTDiscus, Cochrane Central Register of Controlled Trials, trial registries, reference lists and citation tracking. Semi-structured interviews with world experts and a patient survey. ELIGIBILITY CRITERIA: Randomised controlled trials (RCTs) evaluating any intervention for people with PHP in any language were included subject to strict quality criteria. Trials with a sample size greater than n=38 were considered for proof of efficacy. International experts were interviewed using a semi-structured approach and people with PHP were surveyed online. RESULTS: Fifty-one eligible trials enrolled 4351 participants, with 9 RCTs suitable to determine proof of efficacy for 10 interventions. Forty people with PHP completed the online survey and 14 experts were interviewed resulting in 7 themes and 38 subthemes. There was good agreement between the systematic review findings and interview data about taping (SMD: 0.47, 95% CI 0.05 to 0.88) and plantar fascia stretching (SMD: 1.21, 95% CI 0.78 to 1.63) for first step pain in the short term. Clinical reasoning advocated combining these interventions with education and footwear advice as the core self-management approach. There was good expert agreement with systematic review findings recommending stepped care management with focused shockwave for first step pain in the short-term (OR: 1.89, 95% CI 1.18 to 3.04), medium-term (SMD 1.31, 95% CI 0.61 to 2.01) and long-term (SMD 1.67, 95% CI 0.88 to 2.45) and radial shockwave for first step pain in the short term (OR: 1.66, 95% CI 1.00 to 2.76) and long term (OR: 1.78, 95% CI 1.07 to 2.96). We found good agreement to 'step care' using custom foot orthoses for general pain in the short term (SMD: 0.41, 95% CI 0.07 to 0.74) and medium term (SMD: 0.55, 95% CI 0.09 to 1.02). CONCLUSION: Best practice from a mixed-methods study synthesising systematic review with expert opinion and patient feedback suggests core treatment for people with PHP should include taping, stretching and individualised education. Patients who do not optimally improve may be offered shockwave therapy, followed by custom orthoses.

Heparin/collagen surface coatings modulate the growth, secretome, and morphology of human mesenchymal stromal cell response to interferon-gamma.

The therapeutic potential of human mesenchymal stromal cells (h-MSC) is dependent on the viability and secretory capacity of cells both modulated by the culture environment. Our previous studies introduced heparin and collagen I (HEP/COL) alternating stacked layers as a potential substrate to enhance the secretion of immunosuppressive factors of h-MSCs. Herein, we examined the impact of HEP/COL multilayers on the growth, morphology, and secretome of bone marrow and adipose-derived h-MSCs. The physicochemical properties and stability of the HEP/COL coatings were confirmed at 0 and 30 days. Cell growth was examined using cell culture media supplemented with 2 and 10% serum for 5 days. Results showed that HEP/COL multilayers supported h-MSC growth in 2% serum at levels equivalent to 10% serum. COL and HEP as single component coatings had limited impact on cell growth. Senescent studies performed over three sequential passages showed that HEP/COL multilayers did not impair the replicative capacity of h-MSCs. Examination of 27 cytokines showed significant enhancements in eight factors, including intracellular indoleamine 2, 3-dioxygenase, on HEP/COL multilayers when stimulated with interferon-gamma (IFN-γ). Image-based analysis of cell micrographs showed that serum influences h-MSC morphology; however, HEP-ended multilayers generated distinct morphological changes in response to IFN-γ, suggesting an optical detectable assessment of h-MSCs immunosuppressive potency. This study supports HEP/COL multilayers as a culture substrate for undifferentiated h-MSCs cultured in reduced serum conditions.

Artificial dry surface biofilm models for testing the efficacy of cleaning and disinfection.

Dry surface biofilms (DSB) harbouring pathogens are widespread in healthcare settings, are difficult to detect and are resistant to cleaning and disinfection interventions. Here, we describe a practical test protocol to palliate the lack of standard efficacy test methods for DSB. Staphylococcus aureus DSB were produced over a 12-day period, grown with or without the presence of organic matter, and their composition and viability were evaluated. Disinfectant treatment was conducted with a modified ASTM2967-15 test and reduction in viability, transferability and biofilm regrowth post-treatment were measured. Dry surface biofilms produced over a 12-day period had a similar carbohydrates, proteins and DNA content, regardless of the presence or absence of organic matter. The combination of sodium hypochlorite (1000 ppm) and a microfiber cloth was only effective against DSB in the absence of organic load. With the increasing concerns of the uncontrolled presence of DSB in healthcare settings, the development of effective intervention model in the presence of organic load is appropriate for the testing of biocidal products, while the use of three parameters, log10 reduction, transferability and regrowth, provides an accurate and practical measurement of product efficacy. SIGNIFICANCE AND IMPACT OF THE STUDY: The widespread presence of biofilms on dry surfaces in healthcare settings has been recently documented. These dry surface biofilms (DSB) present an unprecedented challenge to cleaning and disinfection processes. Here, we describe a practical efficacy protocol based on an in vitro Staphylococcus aureus DSB model. The protocol measures reduction in viability, transferability and biofilm regrowth post-treatment to provide altogether a practical assessment of product efficacy against dry surface biofilms.

Decreased placental glypican expression is associated with human fetal growth restriction.

Placental mediated fetal growth restriction (FGR) is a leading cause of perinatal morbidity and mortality. Heparan sulphate proteoglycans (HSPG) are highly expressed in placentae and regulate haemostasis. We hypothesise that altered expression of HSPGs, glypicans (GPC) may contribute to the development of FGR and small-for-gestational-age (SGA). GPC expression was determined in first-trimester chorionic villous samples collected from women with later SGA pregnancies and in placentae from third-trimester FGR and gestation-matched uncomplicated pregnancies. The expression of both GPC1 and GPC3 were significantly reduced in first-trimester SGA as well as in the third-trimester FGR placentae compared to controls. This is the first study to report a relationship between altered placental GPC expression and subsequent development of SGA/FGR.

Decorin expression is decreased in first trimester placental tissue from pregnancies with small for gestation age infants at birth.

Fetal growth restriction (FGR) is a leading cause of perinatal morbidity and mortality. FGR pregnancies are often associated with histological evidence of placental vascular thrombosis. The proteoglycans are important components and regulators of vascular homeostasis. Previous studies from our laboratory highlighted mRNA and protein expression differences in placental proteoglycan decorin (DCN), within a clinically well-characterised cohort of third-trimester idiopathic FGR compared with gestation-matched uncomplicated control pregnancies. We also showed that decorin contributes to abnormal angiogenesis and increased thrombin generation in vitro. These observations suggest that DCN gene expression may contribute to the etiology of FGR. Small for gestational age (SGA) is frequently used as a proxy for FGR and is defined as a birth weight below the 10th percentile of a birth weight curve. We therefore made use of a unique resource of first trimester tissues obtained via chorionic villus sampling during the first trimester to investigate the temporal relationship between altered DCN expression and any subsequent development of SGA. We hypothesized that placental DCN expression is decreased early in gestation in SGA pregnancies. Surplus chorionic villus specimens from 15 women subsequently diagnosed with FGR and 50 from women with uncomplicated pregnancies were collected. DCN mRNA and DCN protein were determined using real-time PCR and immunoblotting, respectively. Both DCN mRNA and protein were significantly decreased in placentae from first-trimester SGA-pregnancies compared with controls (p < 0.05). This is the first study to report a temporal relationship between altered placental DCN expression and subsequent development of SGA.

Current Views on Clinical Oncology Training from the 2015 Oncology Registrars' Forum Survey.

The major role of the Oncology Registrars' Forum (ORF) of the Royal College of Radiologists is to voice the opinions of the clinical oncology trainee body and work towards improving all aspects of clinical oncology training in the UK. In order to provide data to support these efforts, the ORF undertakes a biennial survey of all trainees. As with the previous surveys, this year's ORF survey produced data that highlight areas of good training as well as new and ongoing areas of concern. This summary highlights the key survey results and provides recommendations for improving the delivery of clinical oncology training in the UK.

LNK (SH2B3): paradoxical effects in ovarian cancer.

LNK (SH2B3) is an adaptor protein studied extensively in normal and malignant hematopoietic cells. In these cells, it downregulates activated tyrosine kinases at the cell surface resulting in an antiproliferative effect. To date, no studies have examined activities of LNK in solid tumors. In this study, we found by in silico analysis and staining tissue arrays that the levels of LNK expression were elevated in high-grade ovarian cancer. To test the functional importance of this observation, LNK was either overexpressed or silenced in several ovarian cancer cell lines. Remarkably, overexpression of LNK rendered the cells resistant to death induced by either serum starvation or nutrient deprivation, and generated larger tumors using a murine xenograft model. In contrast, silencing of LNK decreased ovarian cancer cell growth in vitro and in vivo. Western blot studies indicated that overexpression of LNK upregulated and extended the transduction of the mitogenic signal, whereas silencing of LNK produced the opposite effects. Furthermore, forced expression of LNK reduced cell size, inhibited cell migration and markedly enhanced cell adhesion. Liquid chromatography-mass spectroscopy identified 14-3-3 as one of the LNK-binding partners. Our results suggest that in contrast to the findings in hematologic malignancies, the adaptor protein LNK acts as a positive signal transduction modulator in ovarian cancers.

Altered decorin leads to disrupted endothelial cell function: a possible mechanism in the pathogenesis of fetal growth restriction?

OBJECTIVE: Fetal growth restriction (FGR) is a key cause of adverse pregnancy outcome where maternal and fetal factors are identified as contributing to this condition. Idiopathic FGR is associated with altered vascular endothelial cell functions. Decorin (DCN) has important roles in the regulation of endothelial cell functions in vascular environments. DCN expression is reduced in FGR. The objectives were to determine the functional consequences of reduced DCN in a human microvascular endothelial cell line model (HMVEC), and to determine downstream targets of DCN and their expression in primary placental microvascular endothelial cells (PLECs) from control and FGR-affected placentae. APPROACH: Short-interference RNA was used to reduce DCN expression in HMVECs and the effect on proliferation, angiogenesis and thrombin generation was determined. A Growth Factor PCR Array was used to identify downstream targets of DCN. The expression of target genes in control and FGR PLECs was performed. RESULTS: DCN reduction decreased proliferation and angiogenesis but increased thrombin generation with no effect on apoptosis. The array identified three targets of DCN: FGF17, IL18 and MSTN. Validation of target genes confirmed decreased expression of VEGFA, MMP9, EGFR1, IGFR1 and PLGF in HMVECs and PLECs from control and FGR pregnancies. CONCLUSIONS: Reduction of DCN in vascular endothelial cells leads to disrupted cell functions. The targets of DCN include genes that play important roles in angiogenesis and cellular growth. Therefore, differential expression of these may contribute to the pathogenesis of FGR and disease states in other microvascular circulations.

Epidemiology of major burns at the Lebanese Burn Center in Geitawi, Lebanon.

Burn care is one of the few areas in medicine considered both medically and surgically challenging, with burn injuries affecting people of all ages and both sexes. Between May 1992 and March 2012, 1,524 patients were admitted to the Lebanese Burn Center in Geitawi, with an average length of stay (LOS) of 36.5 days. The most frequently encountered injuries were thermal burns, generally resulting from domestic accidents. Of our patients, 47% were from rural areas and burned body surface (BBS) was the most serious factor, with 36% of all those admitted having suffered burns of 20% to 40% of their total body surface area (TBSA). Our team of experienced physicians, nurses, nutritionists and physical therapists was essential to successful burn care and outcomes were improved with adequate early fluid intake. The main causes of death were multiple organ failure due to hemodynamic instability, followed by respiratory failure from inhalation injury. A week after the injury, risk of infection was the main threat to the burn victims. Although this threat was compounded by malnutrition and immunodeficiency, excessive use of antibiotics was not justified. The fatality rate was about 18% and correlates with higher TBSA burns.

Le traitement des brûlés est l'un des rares domaines de la médecine qui sont à la fois médicalement et chirurgicalement difficiles. En plus, les brûlures affectent les personnes de tous âges et des deux sexes. Entre mai 1992 et mars 2012, 1.524 patients ont été admis au Centre des Brûlés libanais à Geitawi. La durée moyenne de séjour (DMS) était de 36,5 jours. Les blessures les plus fréquemment rencontrées sont des brûlures thermiques, et la plupart des brûlures étaient dues à des accidents domestiques. De nos patients, 47% viennent de zones rurales. La surface corporelle brûlée (SCB) était le facteur le plus grave: 36% des patients avaient des brûlures sur 20% à 40% de la surface corporelle totale (TBSA). Notre équipe de médecins expérimentés, d'infirmières, de nutritionnistes, et de physiothérapeutes a été essentiel au succès du traitement des brûlures. En plus, les résultats sont améliorés avec l'apport hydrique précoce et adequat. L'instabilité hémodynamique était la cause principale de décès en provoquant la défaillance multiviscérale. La seconde cause de décès était l'insuffisance respiratoire due à l'inhalation. Après le septième jour, le risque d'infection était la menace principale pour la victime de brûlures, et ce risque est aggravé par la malnutrition et l'immunodéficience. Tout le même, cela ne justifie pas l'utilisation excessive des antibiotiques. Le taux de létalité était d'environ 18% en corrélation avec TBSA.

PIAS4 is an activator of hypoxia signalling via VHL suppression during growth of pancreatic cancer cells.

BACKGROUND: The PIAS4 protein belongs to the family of protein inhibitors of activated STAT, but has since been implicated in various biological activities including the post-translational modification known as sumoylation. In this study, we explored the roles of PIAS4 in pancreatic tumourigenesis. METHODS: The expression levels of PIAS4 in pancreatic cancer cells were examined. Cell proliferation and invasion was studied after overexpression and gene silencing of PIAS4. The effect of PIAS4 on hypoxia signalling was investigated. RESULTS: The protein was overexpressed in pancreatic cancer cells compared with the normal pancreas. Gene silencing by PIAS4 small interfering RNA (siRNA) suppressed pancreatic cancer cell growth and overexpression of PIAS4 induced expression of genes related to cell growth. The overexpression of PIAS4 is essential for the regulation of the hypoxia signalling pathway. PIAS4 interacts with the tumour suppressor von Hippel-Lindau (VHL) and leads to VHL sumoylation, oligomerization, and impaired function. Pancreatic cancer cells (Panc0327, MiaPaCa2) treated with PIAS4 siRNA suppressed expression of the hypoxia-inducible factor hypoxia-inducible factor 1 alpha and its target genes JMJD1A, VEGF, and STAT3. CONCLUSION: Our study elucidates the role of PIAS4 in the regulation of pancreatic cancer cell growth, where the suppression of its activity represents a novel therapeutic target for pancreatic cancers.

Overexpression of miR-26a-2 in human liposarcoma is correlated with poor patient survival.

Approximately 90% of well-differentiated/de-differentiated liposarcomas (WDLPS/DDLPS), the most common LPS subtype, have chromosomal amplification at 12q13-q22. Many protein-coding genes in the region, such as MDM2 and , have been studied as potential therapeutic targets for LPS treatment, with minimal success. In the amplified region near the MDM2 gene, our single nucleotide polymorphism (SNP) array analysis of 75 LPS samples identified frequent amplification of miR-26a-2. Besides being in the amplicon, miR-26a-2 was overexpressed significantly in WDLPS/DDLPS (P<0.001), as well as in myxoid/round cell LPS (MRC) (P<0.05). Furthermore, Kaplan-Meier survival analysis showed that overexpression of miR-26a-2 significantly correlated with poor patient survival in both types of LPS (P<0.05 for WDLPS/DDLPS; P<0.001 for MRC). Based on these findings, we hypothesized that miR-26a-2 has an important role in LPS tumorigenesis, regardless of LPS subtypes. Overexpression of miR-26a-2 in three LPS cell lines (SW872, LPS141 and LP6) enhanced the growth and survival of these cells, including faster cell proliferation and migration, enhanced clonogenicity, suppressed adipocyte differentiation and/or resistance to apoptosis. Inhibition of miR-26a-2 in LPS cells using anti-miR-26a-2 resulted in the opposite responses. To explain further the effect of miR-26a-2 overexpression in LPS cells, we performed in silico analysis and identified 93 candidate targets of miR-26a-2. Among these genes, RCBTB1 (regulator of chromosome condensation and BTB domain-containing protein 1) is located at 13q12.3-q14.3, a region of recurrent loss of heterozygosity (LOH) in LPS. Indeed, either overexpression or inhibition of RCBTB1 made LPS cells more susceptible or resistant to apoptosis, respectively. In conclusion, our study for the first time reveals the contribution of miR-26a-2 to LPS tumorigenesis, partly through inhibiting RCBTB1, suggesting that miR-26a-2 is a novel therapeutic target for human LPS.

miR-34a functions as a tumor suppressor modulating EGFR in glioblastoma multiforme.

Chromosome 1p36.23 is frequently deleted in glioblastoma multiforme (GBM). miR-34a localizes in this region. Our experiments found that miR-34a was often deleted and epidermal growth factor receptor (EGFR) was frequently amplified in genomic DNA of 55 GBMs using single-nucleotide polymorphism DNA microarray. Notably, we found that the mean survival time was significantly shortened for patients whose GBMs had both EGFR amplification and miR-34a deletion. Expression of miR-34a was significantly lower in GBM samples compared with normal brain tissue. Forced expression of miR-34a in GBM cells decreased their ability to migrate and profoundly decreased their levels of cyclin-A1, -B1, -D1, and -D3, as well as cyclin-dependent kinase and increased expression of cyclin kinase inhibitor proteins (p21, p27). Also, human GBM cells (U251) stable overexpressing mir-34a formed smaller tumors when growing as xenografts in immunodeficient mice compared with wild-type U251 GBM cells. Furthermore, the protein expression of EGFR decreased in the cells with forced overexpression of miR-34a. Additional studies showed that mir-34a targeted Yin Yang-1 (YY1) and YY1 is a transcription factor that can stimulate the expression of EGFR. Thus, our data suggest that miR-34a acts as a tumor suppressor by inhibiting growth of GBM cells in vitro and in vivo associated with moderating the expression of cell-cycle proteins and EGFR. Moreover, we discovered for the first time that both deletion of miR-34a and amplification of EGFR were associated with significantly decreased overall survival of GBM patients.